Bloomberg vs Peterffy
Bloomberg L.P. and Interactive Brokers.
The differences
- Forbes puts Thomas Peterffy about $12.2B ahead of Michael Bloomberg.Forbes figures from 5 Sep 2026 and 9 Oct 2026.
- Both started the company their money comes from.
- Michael Bloomberg has signed the Giving Pledge; Thomas Peterffy has not.
- Michael Bloomberg has held a public or government advisory role; Thomas Peterffy has none on record.
Put someone else on either side
Side by side
Bloomberg
PeterffyThe money
- Net worth, Forbes
- $94.9BForbes, 9 Oct 2026
- $107BForbes, 5 Sep 2026
- Net worth, Bloomberg
- Not stated
- $104BBloomberg, 11 Oct 2026
- Forbes rank
- No. 20Real-Time list, 9 Oct 2026
- No. 20Real-Time list, 5 Sep 2026
- Billionaire since
- Not stated
- Not stated
Where it came from
- How it started
- Founded itFounded Bloomberg L.P. in 1981 after leaving Salomon Brothers; Forbes says he put in the seed funding
- Founded itFormed the business now known as Interactive Brokers in 1977 after buying an American Stock Exchange seat
- Main source
- Bloomberg L.P.
- Interactive Brokers stock, held through IBG HoldingsBloomberg: 'The majority of Thomas Peterffy's fortune is derived from Interactive Brokers Group'
- Companies
- Bloomberg L.P.Bloomberg L.P.: Founder and majority owner
- Interactive BrokersInteractive Brokers: Founder and chairman
- Biggest stake
- Bloomberg L.P.88% owned
- Interactive Brokers67.5% owned
The person
- Born
- 14 Feb 1942Boston, Massachusetts, United States
- 1944Budapest, Hungary
- Country
- United StatesLives in New York City, United States
- United StatesLives in Palm Beach, Florida, United States
- Education
- Graduate degreeBS in electrical engineering, Johns Hopkins University; MBA, Harvard Business School (1966)
- Left university without a degreeAttended the College of Surveying in Hungary; studied at New York University without finishing
- Parents
- Grew up in a middle-class home in Medford, Massachusetts; worked in a parking lot and took government loans to pay for Johns HopkinsParents' occupations not stated
- Descended from Hungarian aristocrats who lost nearly everything under Soviet rule; arrived in the US in 1965 at 21 with no moneyForbes profile; parents' occupations not stated
What they give
- Giving Pledge
- Signed in 2010
- Not a signer
- Foundation
- Bloomberg PhilanthropiesCovers his foundation, corporate and personal giving
- Peterffy FoundationEstablished by Peterffy and run by his children; funds the Living Forest Project, Reweaving the Web and One Small Planet
- Lifetime giving
- $25.4BForbes, 31 Dec 2025. Forbes' estimate of lifetime giving through the end of 2025, counting only money given to charitable recipients
- Not stated
Role and record
- Role now
- OwnerFounder and majority owner of Bloomberg L.P.; founder of Bloomberg Philanthropies; UN Special Envoy on Climate Ambition and Solutions
- Chair of the boardFounder and chairman of Interactive Brokers
- Successor
- Vlad Kliatchko, CEO since 2023 and chairNo ownership successor or family executive named in the cited sources
- Milan Galik succeeded him as CEO in 2019His son William Peterffy, CEO of One Small Planet, is an Interactive Brokers director
- Public office
- Mayor of New York City; UN Special Envoy on Cities and Climate Change; UN Special Envoy for Climate Action, later Special Envoy on Climate Ambition and Solutions; WHO Global Ambassador for Noncommunicable Diseases and Injuries2002-2013; 2014; 2018-present; 2016-present
- None found
- Legal record
- None found
- 1980: American Stock ExchangeSettled an exchange disciplinary matter over exceeding options position limits (Rule 904) with a $500 fine, per his FINRA BrokerCheck report.
